OpenFOAM/foam has its own warnings and errors that can be used in the code.
The warnings are defined as macros in
$FOAM_SRC/OpenFOAM/messageStream.H for OpenFOAM, and
$FOAM_SRC/foam/messageStream.H for foam-extend. The error message stream macros are located in
error.H, it can also be found in $FOAM_SRC/OpenFOAM/lnInclude or $FOAM_SRC/foam/lnInclude, depending on the OF version used.
They can be used in the code, together with the formatting described in the article How to get function names from within functions in C++ for example like this:
if(mesh.nCells() > 64 * 64 * 64) WarningIn(__PRETTY_FUNCTION__) << "RBF system factorization is memory intensive: NxN x nCells x 64 bits.\n";
The result is:
Create time Create mesh for time = 0 --> FOAM Warning : From function int main(int, char**) in file lentTestrbfCellsInterpolationEigen.C at line 128 RBF system factorization is memory intensive: NxN x nCells x 64 bits.